Grilled meat restaurants or grilled chicken restaurants are filled with smoke and smell of meats or other food materials and the smell stays on clothes and hair, because of which people dressed up in formal attire or expensive coats hesitate to enter these restaurants.
To attract more customers, especially female customers, hooded type roasters, wherein a hood is installed directly above the grill to suck smoke rising from the meat and other food materials placed on the grill, and, smokeless meat roasters, wherein a suction hole is provided on the periphery of the grill to suck smoke generated from the food materials from a side of the grill, have been used.
The former, the hooded type, has the drawbacks that the generated smoke is not completely sucked, and that the air-conditioning efficiency is lowered because the roaster also sucks in the conditioned room air.
The latter, the smokeless meat roaster, has the problem that the moisture on the heated food materials and the room air are also sucked in together with smoke through the suction hole located on the side above the grill, thereby drying up the grilled food materials to harm the taste thereof.
To solve the above problems of the conventional devices, the present inventors have previously disclosed a cooking device with a smoke exhaust system in Japanese Examined Patent Publication No. Sho 59-49004. In a cooking device having its heat source on the lower side, as the smoke generated from food materials rises upwardly, it appears to be generated from the entire surface of the food materials. However, most of the smoke is actually generated from the part of the food materials nearest to the heat source, that is, the underside of the food materials. The invention was made based on the finding. According to the invention, smoke is collected from a suction hole provided around the grill on the lower side thereof and exhausted through a duct. The invention thus provided a cooking device that hardly generates smoke.
However, most of the prior art including the above-mentioned cooking device with a smoke exhaust system disclosed in Japanese Examined Patent Publication No. Sho 59-49004 as well as the above-described hooded type roasters or smokeless meat roasters have a structure wherein the smoke sucked into a duct is directly exhausted to the outdoors. With this system, the smoke and smell exhausted to the outdoors cause a great impact on the surrounding environment. Another problem is that oil components contained in the smoke are adhered to the inside of the duct and steadily accumulated therein. Furthermore, ducts arranged in a complicated layout cannot be cleaned, which leads to constant danger of fire. In addition, large-scale duct installation work is required to open a grilled meat restaurant in a multi-storied building, which sometimes hinders such restaurant from opening.
In some gas roasters, there are non-duct type roasters using an electric dust collector; however, where gas is used as a heat source, generation of NOx cannot be suppressed with such an electrostatic dust collecting system. Therefore, when the air dedusted by the electric dust collector is exhausted outside (into the interior of the restaurant), it causes irritation and itchiness in eyes, which currently is a problem in actual use.